A Secure Private Information Retrieval in Cloud Environment
Yang HaiBin, Ling Zhang · 2016
Private information retrieval is an important application of homomorphic encryption. As a hot topic in recent years, homomorphic encryption scheme can operate on the ciphertext and the decryption result is equal to the same operation on the plaintext. Trivial PIR protocol faces the plaintext retrieval, so it could not guarantee the database privacy. In the cloud environment, it is unsafe to store the plaintext in the server. In order to settle the above problem, based on a somewhat homomorphic encryption scheme, we design a multi-server PIR. It can not only achieves the privacy and resisting the colluding attack, but also reaches the information-theoretic security.